This invention relates to a method of producing a cover-packing assembly which comprises forming a rubber packing on a cover member for a hard disk device and, simultaneously with the formation, adhering the rubber packing firmly to the cover member.
2. Description of the Prior Art
A hard disk device generally comprises disks of an aluminum alloy or the like coated with a magnetic material which are enclosed in a sealed container, and magnetic heads each disposed close to the disk, with an about 0.2- to 0.5-.mu.m gap therebetween, for recording and reproduction of information into and from the disks.
In the hard disk device, it is necessary to prevent head crash, breakage of magnetic surfaces of the disks or the like troubles from occurring due to the dust present in the device or coming into the device from the outside.
In order to obviate such troubles, therefore, there has been used a system in which air is circulated in the sealed container through a high performance filter, for pressure regulation and cleaning of air, and a sealing packing is provided between each cover (top cover, down cover, etc.) and the container.
As the known packing of this type, there have hitherto been packing members molded from, or die-cut from a molded sheet of, neoprene rubber, urethane rubber, silicone rubber, nitrile-butadiene rubber, etc., and packing members die-cut from foam sheets of these rubbers, polyethylene, etc.
Where such a molded or die-cut rubber product or the like is used as the packing member, however, there is need for troublesome work, for instance, the preliminary adhesion of a release paper to the packing by a pressure sensitive adhesive or the use of an adhesive in applying the packing member to the cover member. In addition, accurate positioning of the cover member and the packing member is difficult to carry out and requires man power or skill, leading to a great loss and, inevitably, to a disadvantage on an economical basis.
Furthermore, with regard to cleanliness required also of the packing member itself, the contamination by a pressure sensitive adhesive, an adhesive or the like used for joining the packing member and the cover member is difficult to avoid. Particularly, the use of a molded packing member involves the problem of slippage arising from defective finishing of flashes, whereas the use of a foamed packing member has the problem of dropping of the dust having penetrated into the cell portions.